This invention relates generally to a constant velocity universal joint. More particularly, it relates to a constant velocity universal joint having a gear type centering device and a boot type seal. The universal joint is applicable to any installation which requires power transfer between non-colinear members. It is particularly applicable for use in on- or off-highway vehicles.
A common universal joint used to transmit motion between two angularly misaligned rotating shafts is the cardan joint. There are however, many applications to which such a joint is not well suited. One such application is where the motion transmission characteristics of the cardan joint, which are non-uniform, result in unacceptable velocity fluctuation between the input and output shafts. One typical solution to this problem is to provide a pair of cardan joints properly phased so as to cancel such velocity fluctuations.
Where weight or size is of primary importance, or where geometry prevents the usual phasing, a constant velocity or double cardan universal joint normally is used. With such a universal joint, constant velocity is assured by the use of a centering device which restricts the associated cardan joints to mutually equal operating angles.
There remains a need in the art to provide a constant velocity universal joint which is smaller, lighter and more durable than universal joints previously known. There is also a need to provide a seal for the centering device of such a universal joint which will seal sufficiently well to retain and distribute lubricant and excluse contamination, thereby prolonging joint life.